Method and device for detecting the phase of a signal via a hybrid coupler, using a test signal

Abstract

In an embodiment method, a hybrid coupler comprises a first input receiving an analog signal, a second input receiving an additional analog signal phase shifted by 90° from the analog signal, and first and second outputs. The method comprises injecting into the second output a test signal having an initial test phase, iteratively generating a current test phase for the test signal, from the initial test phase to a final test phase equal to the initial test phase increased by at least one portion of one complete revolution, and, in each iteration, measuring the current peak value of the first output, and storing the current test phase and the current peak value as a maximum/minimum peak value if there is not a stored maximum/minimum peak value higher/lower than the current peak value, respectively, and determining a phase of the analog signal from the stored test phase.

The invention claimed is: 
     
       1. A method of operating a hybrid coupler in a power-combiner mode, the method comprising:
 receiving, at a first input of the hybrid coupler, a first analog signal; 
 receiving, at a second input of the hybrid coupler, an additional analog signal that is phase shifted by 90° with respect to the first analog signal; 
 injecting, into a second output of the hybrid coupler, a test signal having an initial test phase; 
 iteratively generating a current test phase for the test signal, from the initial test phase to a final test phase equal to the initial test phase increased by at least one portion of one complete revolution, and, in each iteration:
 measuring a current peak value of an output signal from a first output of the hybrid coupler; and 
 storing in memory the current test phase and the current peak value as a maximum peak value or a minimum peak value in response to there not being a stored maximum peak value higher or a stored minimum peak value lower than the current peak value, respectively; and 
 
 determining a phase of the first analog signal from the stored test phase. 
 
     
     
       2. The method as claimed in  claim 1 , wherein the phase of the first analog signal is equal to:
 the stored test phase, in response to the stored test phase corresponding to the stored maximum peak value; or 
 the stored test phase increased by 180°, in response to the stored test phase corresponding to the stored minimum peak value. 
 
     
     
       3. The method as claimed in  claim 1 , wherein the final test phase is the initial test phase increased by one complete revolution. 
     
     
       4. The method as claimed in  claim 1 , further comprising:
 comparing a setpoint phase and the phase of the first analog signal; and 
 in response to the setpoint phase and the determined phase of the first analog signal being different, adjusting the phase of the first analog signal until the setpoint phase and the phase of the first analog signal are equal to within a tolerance. 
 
     
     
       5. The method as claimed in  claim 4 , wherein the tolerance is 5 to 10%. 
     
     
       6. The method as claimed in  claim 4 , wherein the tolerance is 5%. 
     
     
       7. An electronic device, comprising:
 a hybrid coupler configured to operate in a power-combiner mode, the hybrid coupler comprising:
 a first input configured to receive a first analog signal; 
 a second input configured to receive an additional analog signal that is phase shifted by 90° with respect to the first analog signal; 
 a first output configured to provide an output signal; and 
 a second output; 
 
 a detecting circuit configured to:
 inject, into the second output, a test signal having an initial test phase; 
 iteratively generate a current test phase for the test signal, from the initial test phase to a final test phase equal to the initial test phase increased by at least one portion of one complete revolution, and, in each iteration:
 measure a current peak value of the output signal; and 
 store in memory the current test phase and the current peak value as a maximum peak value or a minimum peak value in response to there not being a stored maximum peak value higher or a stored minimum peak value lower than the current peak value, respectively; and 
 
 determine a phase of the first analog signal from the stored test phase. 
 
 
     
     
       8. The electronic device as claimed in  claim 7 , wherein the phase of the first analog signal is equal to:
 the stored test phase in response to the stored test phase corresponding to the stored maximum peak value; or 
 the stored test phase increased by 180° in response to the stored test phase corresponding to the stored minimum peak value. 
 
     
     
       9. The electronic device as claimed in  claim 7 , wherein the final test phase is the initial test phase increased by one complete revolution. 
     
     
       10. The electronic device as claimed in  claim 7 , further comprising:
 an adjusting circuit coupled to the hybrid coupler, and configured to:
 deliver to the first input the first analog signal; 
 deliver to the second input the additional analog signal; and 
 deliver to the detecting circuit a setpoint signal having a setpoint phase; 
 
 wherein the detecting circuit is further configured to:
 compare the setpoint phase and the determined phase of the first analog signal; and 
 in response to the setpoint phase and the determined phase of the first analog signal being different, adjust the phase of the first analog signal via the adjusting circuit until the setpoint phase and the determined phase of the first analog signal are equal to within a tolerance. 
 
 
     
     
       11. The electronic device as claimed in  claim 10 , wherein the adjusting circuit comprises a complementary hybrid coupler configured to operate in a power-divider mode and coupled to the first and second inputs of the hybrid coupler. 
     
     
       12. The electronic device as claimed in  claim 10 , wherein the adjusting circuit comprises a complementary hybrid coupler configured to operate in a power-divider mode and coupled to the first and second inputs of the hybrid coupler via a coupling stage. 
     
     
       13. The electronic device as claimed in  claim 10 , wherein the tolerance is 5 to 10%. 
     
     
       14. The electronic device as claimed in  claim 10 , wherein the tolerance is 5%. 
     
     
       15. An apparatus, comprising:
 an electronic device comprising:
 a hybrid coupler configured to operate in a power-combiner mode, the hybrid coupler comprising:
 a first input configured to receive a first analog signal; 
 a second input configured to receive an additional analog signal that is phase shifted by 90° with respect to the first analog signal; 
 a first output configured to provide an output signal; and 
 a second output; 
 
 a detecting circuit configured to:
 inject, into the second output, a test signal having an initial test phase; 
 iteratively generate a current test phase for the test signal, from the initial test phase to a final test phase equal to the initial test phase increased by at least one portion of one complete revolution, and, in each iteration:
 measure a current peak value of the output signal; and 
 store in memory the current test phase and the current peak value as a maximum peak value or a minimum peak value in response to there not being a stored maximum peak value higher or a stored minimum peak value lower than the current peak value, respectively; and 
 
 
 determine a phase of the first analog signal from the stored test phase; and 
 
 an antenna coupled to the hybrid coupler. 
 
     
     
       16. The apparatus as claimed in  claim 15 , wherein the apparatus is a communication apparatus. 
     
     
       17. The apparatus as claimed in  claim 15 , wherein the phase of the first analog signal is equal to:
 the stored test phase in response to the stored test phase corresponding to the stored maximum peak value; or 
 the stored test phase increased by 180° in response to the stored test phase corresponding to the stored minimum peak value. 
 
     
     
       18. The apparatus as claimed in  claim 15 , wherein the final test phase is the initial test phase increased by one complete revolution. 
     
     
       19. The apparatus as claimed in  claim 15 , wherein the electronic device further comprises:
 an adjusting circuit coupled to the hybrid coupler, and configured to:
 deliver to the first input the first analog signal; 
 deliver to the second input the additional analog signal; and 
 deliver to the detecting circuit a setpoint signal having a setpoint phase; 
 
 wherein the detecting circuit is further configured to:
 compare the setpoint phase and the determined phase of the first analog signal; and 
 in response to the setpoint phase and the determined phase of the first analog signal being different, adjust the phase of the first analog signal via the adjusting circuit until the setpoint phase and the determined phase of the first analog signal are equal to within a tolerance. 
 
 
     
     
       20. The apparatus as claimed in  claim 19 , wherein the adjusting circuit comprises a complementary hybrid coupler configured to operate in a power-divider mode and coupled to the first and second inputs of the hybrid coupler. 
     
     
       21. The apparatus as claimed in  claim 19 , wherein the adjusting circuit comprises a complementary hybrid coupler configured to operate in a power-divider mode and coupled to the first and second inputs of the hybrid coupler via a coupling stage. 
     
     
       22. The apparatus as claimed in  claim 19 , wherein the tolerance is 5 to 10%.